Phenol-formaldehyde resins for foaming compositions



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PHENOL-FORMALDEHYDE RESINS FOR FDAMING COMPOSITIONS Eli Simon, Los Angeles, and Frank W. Thomas, Burbank, Califi, assignors to Lockheed Aircraft Corporation, Burbank, Calif.

No Drawing. Application November 1, 1952, Serial No. 318,324

7 Claims. (Cl. 260-43) 2,728,741 Patented Dec. 27, 1955 quired. It has been found'that the physical strength properties of the foamed or cellular plastic products may be controlled to a considerable extent by varying or adjusting the specific gravity of the phenolic resins employed. Thus the specific gravity of the phenolic resin may be varied I between 1.15 and 1.35 to attain the desired range or type of physical and chemical properties required in the cellular plastic material.

The reaction of a given phenol with a specific aldehyde takes place in accordance with the established and well known methods. However, the resins are condensed in the presence of the alkaline catalyst of the invention which is a mixture of two alkalies or bases, namely sodium hydroxide and barium hydroxide. The molar proportions or This invention relates to reactant foaming compositi f th lk li are f 2,() 1()4 l t 1,0)(10- lions or mixtures for Producing 661111131 P i Pf mols of the barium hydroxide octahydrate to from 1X10- and to improvcdphenolic resins for incorporation 1n such l to -z l f the sodium hydroxide Best lflg zip c-l h u I 1 d d sults have been obtained where the alkalies are used in the We ave iSCOVeYe t at C6 11 H P astlc P llcts all proportion of 1.27 10- mols barium hydroxide octahymaterials of superior physical properties and greater unid t d 1 6 1()2 l f th di h d id W formity of cell structure are obtained when the phenolic h di d h h h phgnolic resins are h resins p p y Fondellsiflg them in the Presence sized employing the catalyst of the invention, with the a speclal catalyst mlX tufe OI y have also bases or alkalies utilized within the proportions or ranges dlscoverod that the foaming pheflollc RS111 mlxflll'es P just given, they result in the production of cellular foamed p w Such resms are conslderably slower to react, products or materials of excellent physical properties and ermittin the cellular products to be poured or formed of uniform cellular structure even in large sections, the much larger sectwns and l g conslderably more reactant or foaming m1xtures being prepared as described tll'l'le flol. the handlmgfand pouring 0f tthe m ft rtilst below. Howeyer, vsl je haie fOlLnd that these dlleasirable recons1 erations are 0 ma or lmpor a e n 6 ac 11a su ts are noto taina lew eret eran es of the ariumh production of commercial products and in production line d id octahydrate nd th sodium hydroxide diff agoperations. The phenolic resins are acid catalyzable and preciably f th ranges given b ve, water miscible ICSOlS characterized by the alkaline cata- In preparing a typical phenolic resin for use in making lyst employed in the synthesis or preparation of the resins. h ll l plastic m t ials, a ixtu f;

It is, therefore, an object of this invention to provide improved phenolic resins or resols, for incorporation in Aphenol lmol. foaming mixtures for making cellular plastic materials and @Efiifigfig ggfggggg gg products, which promote or insure the production of supehydroxide catalyst 1.01 x 10 to 2.02 x 10- mols. rior cellular plastics and that facilitate the mixing, 10 to 50% 0mm charge handling and pourmg of the foaming mixtures or compo- 40 is placed in a suitable reactor, the components being coml h f th bined in the proper sequence. The resin is cooked in the It 18 allot if 0 P 0 e il tohprovl e f i presence of the alkaline catalyst for the required time, neuor 'f P enohc rfism t at are re u y tralized to a pH of from 6.8 to 7 and then stripped to a slow 1n their rates of rise or reaction rates so as to be more Suitable viscosity readily Poured applied and so as to be suitable? for the The following are illustrative formulations of the pheof artlfiles, and P of large serftlon' a nolic resins of the invention suitable for incorporation in e re,sms e fi fi g g' f f from the foaming compositions for making the cellular plastic ii}: P eno i en. Y ffg products, the catalyst recited in these formulations being a p t ion 15 eterm,me e the barium hydroxide-sodium hydroxide catalyst dedesired specific gravlty, v1scos1ty and water nusclblht-y of p scribed above. 1

the resin or resol and is governed to some extent by the 1mproved catalyst. The phenolic resins which we employ in the foaming mixtures for producing the cellular plastic 1 (species typ d and e) (a) Mols (b) Mols (c) Mols (d) Mols (e) Mols Phenol 1.0 1.0 1.0 i 1.0 1.0 Formaldehyde 1. 5 1. 5 1. 5 2, 0 1 2 Ba(OH) 8H;O 1.27 10- 1.5 10 1.1 10-* 2x10- 1 10 NaOH 1.6 10- 1.0 10 1.4 10 1.s 10- 1 s 10s products are acid catalyzable water miscible resol type re's- In the following examples or formulations the ranges of ins that are the reaction products of phenolic types of com proportions of the barium hydroxide and Sodium Y pounds such as polyhydric phenols; phenol; amino phenols; lde are from: V

halogen, amino, carboxy, nitro, saturated or unsaturated Ba(OH)2 8H2O to 2x104 alkyls or aryl substituted phenols, with aldehydes such as NaOH 1 to -2 formaldehyde, alkyl-aldehydes, aryl aldehydes, poly aldehydes, furan aldehydes, amino or halo aldehydes, nitro substituted aldehydes, etc. 'Any combination of these with alkyd or aryl amines, aldoses, alcohols or epoxy compounds may be used when such modification is re- Thus the catalysts of the following examples are prepared from the barium hydroxide and. sodium hydroxide employed in theproportion ranges, just specified, of the totalresin components or ingredients.

Resin 2 Para-isopropyl phenol 1 mol.

Formaldehyde 1 to 2.5 mols.

Catalyst.

Resin 3 1 mol total g gfig gghe 1?, rgsec but yliden egiphgnp mg m e proper ion om o Butyhdenedipheno 75% by mol weight) Formaldehyde 1 to 2.5'mols.

Catalyst.

Resin 4 1 mol total 4 Phenol (the 0,0diphenol being in the pro- O, Odiphenol portion of from 5 to 75% by mol Weight).

Formaldehyde 1 to 2.5 mols.

yst.

Resin 5 1 mol total Phenol (the parachloro phenol being in the Parachloro phenol proportion of from 5 to 75% by mol welght).

Formaldehyde l to 2.5 mols.

Catalyst.

Resin 6 1 mol total Parahydroxy benzoic acid (the parahydrom bcnzoic acid being Phenol in the proportion of from 5 to 75% by mol weight).

Formaldehyde 1 to 2.5 mols.

C alyst.

Resin 7 Phenol 1 mol total Cresol (ortho, meta, para or (the cresol being in the proportion of mixture thereof) from 5 to 75% by mol weight).

Formaldehyde 1 to 2.5 mols.

Catalyst.

Resin 8 Phenol 1 mol.

Formaldehyde furfural 1 to 2.5 mols total (the furiural being in the proportion of from 5 to 50% by mol Weight).

Catalyst.

Resin 9 Phenol 1 mol.

1 to 2.5 mols total Acctaldehyde (the aceteldehyde being in the pro- Formaldehyde portion of from 5 to 50% by mol weight).

Catalyst.

Resin 10 Phenol 1 mol.

1 to 2.5 mols total Benzaldehyde (the benzaldehydc being in the pro Formaldehyde portion of from 5 to 50% by mol weight).

Catalyst.

Resin 11 1 mol total Phenol (the para nitro phenol being in the Para (ortho) nitro phenol prqplolrzgion of from 5 to 75% by mol weig Formaldehyde 1 to 2.5 mols.

Catalyst.

Resin 12 1 mol total $5236 beta) naptho] (the napthol being in the prolportion of from 5 to 75% by mol weig t). Formaldehyde 1 to 2.5 mols. Catalyst.

Resin 13 Phenol 1 mol.

Methyl ethyl 0.5 to 1 mol.

Formaldehyde.... 1 to 2.5 mols.

Catalyst.

Resin 14 Phenol 1 mol.

Dextrose 0.5 to 1 mol.

Formaldehyde 1 to 2.5 mols.

Catalyst.

Resin 15 Phenol limo].5 1s ta 2. mo to Glyoxal (as polyglyoxal).- .4 a

glyoxal being in the proportion Fmmaldehyde of from 5 to 50% by mol weight).

Catalyst.

Resin 16 Phenol 1 mol. Ortho hydroxybenz 0.5 to 1 mol. Formaldehyde 1 to 2.5 mols. Catalyst.

Resin 1 7 Phenol 1 mol. Furtural 1 to 2.5 mols. Ketone (acetone, methyl ethyl 0.5 to lmol.

ketone). Catalyst.

Resin 18 Phenol 1 mol. 7 Formaldehyde 1 to 2.5 mols. Polyvinyl alcohol 1 to 15% by weight of the total weight I of the phenol and formaldehyde. Catalyst.

Cellular plastics of increased toughness, elasticity and flexibility are obtained When polyvinyl alcohol and/ or polyvinyl alcohol chloride are used in preparing the phenolic resols. The polyvinyl alcohol or chloride is used in the proportion of from 0.5 to 20% by Weight of the combined weight of the other components. In addition to benefiting the physical characteristics or properties of the final cellular plastic product the polyvinyl alcohol serves to control the exothermic temperature during the foaming reaction facilitating the operations and the handling of the mixture during the foaming period. The following typical resin formulations 19 to 28 inclusive, in-- clude polyvinyl alcohol.

Resin 19 Phenol 1 mol. Terpineol. 0.25 to 1 mol. Formaldehyde 1 to 2.5 mols.

atalyst. Polyvinyl alcohol 1 to 15% by weight of the combined weight of the other components.

Resin 20 Sodium benzene sulfonatc 0.5 to 1 mol. Phen m Formaldehyde 1 to 2.5 mols. Catalyst. Polyvinyl alcohol l. to 15% by weight of the combined weight of the other components.

Resin 21 Glycerol. 0.25 to 1 mol.

o1 1 mol.

1 to 2.5 mols. Catalyst. Polyvinyl alcohol 1 to 15% by weight of the combined weight of the other components.

In preparing Resin 21, other polyhydric alcohols, such I 7 as glycols and amino alcohols may be used instead of the a glycerol in the same proportion as the glycerol.

. Resin 22 Phenol 1 mol. Formaldehyde 1 to 2.5 mols. Catalyst. Eplchlorohydrin 5 to 20% by weight of the combined ivelight of the phenol and formaldey 8. Polyvinyl alcohol l to 15% by weight of the combined weight of the other components.

Resin 23 Phenol 1 t t 1 Furfural 0 IDOS 0 8,

(the iurfural being in the proportion Formaldehyde of from 5 to 50% by mol weight). Polyvinyl alcohol 5 to 50 grams. Catalyst.

Resin 24 mol total (t he bisphenol being in the proportion o Phenol"--. 1 Bisphenol A (P, P'propyllde'nefrom 5 to 75% by mol weight).

diphenol weight of the other components.

Resin 25 1 mol total I ol (the P, Pdipheuol being in the pro P, Pdiphenol portion of from to 75% by mol weight). Eplchiorohydrin 0.25 to 1 mol. Formaldehyde 1 to 2.5 mols. Catalyst. Polyvinyl alcohol 1 to 15% by weight of the combined weight of the other components.

Resin 26 1 mol total g (the resorcinol being in the proporesommo tion of from 5 to 75% by mol weight). Formaldehyde..." 1 to 2.5 mole. Catalyst. Polyvinyl alcohol 1 to 15% by weight of the combined weight of the other components.

Resin 27 1 mol total Phenol the catechol being in the proportion Catechm i it from 5 m 75% by mol weight). Formaldehyde 1 to 2.5 mols. Catalyst. Polyvinyl alcohol 1 to 15% by weight of the combined weight of the other components.

Resin 28 Phenol 1 mol. Formaldehyde. i to 2.5 mols :-Propylamine 0.25 to 1 mol.

ata st. Polyv yl alcohol 1 to 15% by weight of the combined weight of the other components.

Where formaldehyde is used in synthesizing any of the above phenolic resols it is preferably employed in an aqueous solution having a formaldehyde concentration of from 30 to 40% by weight, usually about 37% by weight.

In preparing the cellular or foamed plastic materials we mix together a phenolic resin such as above described, a gassing or foaming agent and an acid catalyst to obtain a reactant or foaming mixture that may be poured in place, applied by spatula, blading, or the like, as the conditions of use indicate. In general, the components or ingredients of the foaming mixture are used in the proportion of 120 parts by weight of the phenolic resin, from 0.1 to 2 parts by weight of the foaming agent, and from 15 to 25 parts by weight of the catalyst. It is often preferred to use 0.5 gram of the foaming agent and 20 grams of the catalyst to each 120 grams of the phenolic resin or resol.

The foaming agent or agents employed in preparing the reactant or foaming mixture may be selected from the following:

Aluminum powder Zinc powder Magnesium powder Sodium bicarbonate Ammonium bicarbonate Potassium bicarbonate pp Oxybis benzene sulfonyl hydrazide Di nitroso pentamethylene tetra amine The metal powders are preferably used in the proportion of from 0.1 to 2 grams for each 120 grams of the phenolic resin. The bicarbonates and the pp oxybis benzene sulfonyl hydrazide are preferably employed in the proportion range of from 0.1 to 5 grams per 120 grams of the phenolic resin, and the di nitroso pentamethylene tetra amine is preferably used in the proportion of 0.1 to 1 gram for each 120 grams of the phenolic resol. These foaming or gassing agents may be used separately or in suitable mixtures.

The acid catalyst of the reactant mixture serves to liberate or generate hydrogen, nitrogen, carbon dioxide, or other gas, to produce the foaming of the resin mass and also serves to efiect a cure of the foamed resin. The following are catalysts that We have found to be practical and effective in the reactant resinous mixtures of the invention. 1 The preferred ranges of proportions of the mvidual catalysts are indicated.

1. Hydrochloric acid-6 N aqueous solution From 5 to 15% by weight of the resin II. Benzene sulfonic acid-20% aqueous solution From 5 to 15% by weight of the resin III. Toluene sulfonic acid-20% aqueous solution From 5 to 15% by weight of the resin IV. Potassium acid sulfate aqueous solution From 5 to 15% by weight of the resin V. Catalyst A From to 20% by weight of the resin Catalyst A contains 20% by weight benzene sulfonic acid, 45% by weight ortho phosphoric acid by Weight concentration in an aqueoussolution) and 35% by weight water. In Catalyst A the benzene sulfonic acid, or equivalents thereof such as phenol sulfonic acid, meta benzene disulfonic acid or toluene sulfonic acid, may be used in the proportion of from 5 to 50%, by weight, the 85% aqueous solution of the ortho phosphoric acid may be used in the proportion of from 10 to 75% by weight and the water in the proportion of from 10 to 70% by weight. I

In the following illustrative and typical formulations of the invention for preparing the foaming or reactant mixtures, the proportions of the ingredients are in percentages by weight of the total weight.

Example 1 Per cent Resin No. 1(a) Aluminum leafing powder 0.1 CatalystA 9.9

Example 2 Per cent Resin No. 1(e) 94 Potassium bicarbonate 1 Toluene sulfonic acid (20% aqueous solution) 5 Example 3 Per cent Resin No. 18 90 Di nitroso pentamethylene tetra amine 2 Hydrochloric acid (6N) 2 Catalyst A 6 In preparing the foamed or cellular phenolic resin materials the selected phenolic resin or resol or a selected blend of the resols and the gassing agent, for example a metallic leafing powder, are thoroughly mixed together to form one component or package. Additives such as dyes, fillers, etc. when used are also mixed with these ingredients. In a like manner the barium hydroxide and sodium hydroxide are mixed together to form another component or package. When it is desired to prepare and apply or use the reactant foamed product, these two packages are mixed together and the resultant mixture is then applied by pouring, brushing, blading, dipping, or the like. The foaming reaction which produces the cellular resin product is accompanied by exothermic heat which serves to set the foam or cellular mass and it is usually desirable to post-cure the product for several hours at slightly elevated temperatures.

It is to be understood that the invention is not to be construed as based upon or dependent upon the theories which we have expressed. Nor is the invention to be regarded as limited to the express procedures or materials set forth, these details being given only by way of illustration and to aid in clarifying the invention. We do not regard such specific details as essential to the invention except insofar as they are expressed by way of limitation in the following claims wherein it is our intention to claim all novelty inherent in the invention as broadly as permissible in view of the prior art.

We claim:

1. The condensation product of 1 mol of a phenol, from 1 to 2.5 mols formaldehyde, from 2.0x 10* 111015 to 1.0X10- mols barium hydroxide octahydrate and from 1 10- to 2 10- mols sodium hydroxide, the hydroxides constituting a catalyst.

2. A phenolic resin which is the condensation product of 1 mol of a phenol, from 1 to 2.5 mols formaldehyde, from 1.()1 10- mols to 2.02 10- mols of a catalyst comprising barium hydroxide octahydrate and sodium hydrate in the proportion range of the total charge of from 2.0X10- to 1.0 10 mols of the barium hydroxide to from l 10-' to 2X10" mols of the sodium hydroxide, andwater in the amount of from 10 to 50% of the total. 3. The phenolic resin which is the condensation product of 1 mol phenol, from 1 to 2 mols formaldehyde, from 2X10" to 1.0 10- mols barium hydroxide octahydrate and from 1.8 10 to 1.4 1()* mols sodium hydroxide.

4. A phenolic resin which is the condensation product of 1 mol phenol, 1.5 mols formaldehyde, 1.27 10 mols barium hydroxide octahydrate, and 1.6 10* mols sodium hydroxide.

5. A phenolic resin which is the condensation product of 1 mol phenol, 1.5 mols formaldehyde, 1.5 10 mols barium hydroxide octahydrate, and 1.6 10 mols sodium hydroxide.

6. A phenolic resin which is the condensation product of 1 mol phenol, from 1 to 2.5 mols formaldehyde, polyvinyl alcohol in the amount of from 1 to 15 by weight of the total weight of the phenol and formaldehyde, from 1 to 2 10- mols barium hydroxide octahydrate, and from 1 to 2 10- mols sodium hydroxide.

7. A phenolic resin which is the condensation product of 1 mol phenol, from 0.25 to 1 mol terpineol, from 1 to 2.5 mols formaldehyde, from 1 to 2 10 mols barium hydroxide octahydrate, from 1 to 2 10 mols sodium hydroxide, and polyvinyl alcohol in the amount of from 1 to 15% by weight of the combined weight of the other components.

References Cited in the file of this patent UNITED STATES PATENTS Sterling Aug. 26, 1952 Sterling Feb. 24, 1953 

1. THE CONDENSATION PRODUCT OF 1 MOL OF A PHENOL, FROM 1 TO 2.5 MOLS FORMALDEHYDE, FROM 2.0X10-4 MOLS TO 1.0X10-4 MOLS BARIUM HYDROXIDE OCTAHYDRATE AND FROM 1X10-2 TO 2X10-2 MOLS SODIUM HYDROXIDE, THE HYDROXIDES CONSTITUTING A CATALYST. 